top of page

Why is it so hard to diagnose endometriosis?

Written by Dr. Alice McGee

Almost everyone who has been diagnosed with endometriosis or is under investigation for endometriosis will tell you what a pain the process has been. Not only due to the physical pain they experience from the condition, but also the pain in uncertainty, waiting and the testing needed to finally get diagnosed and finally get some answers. But why is this?

Endometriosis is a very common condition, with estimates of about 10% of women and girls of reproductive age having it! This is roughly 190 million girls and women worldwide. It often goes undetected for many years. Often women who have endometriosis ‘put up’ with their symptoms or have been told that the pain they experience is a normal part of their period or cycle. Symptoms can easily be misdiagnosed as conditions such as irritable bowel syndrome, pelvic inflammatory disease, or irritable bladder. Many women who report chronic pelvic pain (pain in the pelvis) are found to have endometriosis when they have further investigations. Unfortunately, many women suffer with the symptoms of endometriosis for many years before finally getting the answers and help they need. I’ve compiled a list of some of the key reasons and difficulties faced in getting endometriosis diagnosed for both patients and healthcare professionals.

First, lack of information and awareness

Like many different medical conditions in women’s health, endometriosis has been a condition that has been historically neglected. Only in recent years has there been much more focus and a spotlight placed on endometriosis. Numerous celebrities and famous people have come forward and given their own stories and experiences of being diagnosed with, and living with, endometriosis. Charities like Endometriosis UK and Endofound (in the United States) have provided really helpful information for those who may have, and those who are diagnosed with, endometriosis.

Did you know?

Many celebrities have come forward in recent years and spoke about their experiences with endometriosis. For example celebrities like Chrissy Teigen, Whoopi Goldberg, Susan Sarandon, Cyndi Lauper and Emma Bunton, just to name a few!

Endometriosis UK conducted research which showed some startling statistics of how low the general public’s knowledge is on endometriosis. 54% of people do not know what endometriosis is. In their study, 56% of people surveyed could not identify any symptoms of endometriosis. In those that knew that endometriosis is a gynaecological medical condition, 35% could not identify any symptoms of endometriosis.

Women, maybe unsurprisingly, are more aware than men in their knowledge of endometriosis, but 33% of women did not know what endometriosis is and almost 50% of women in the survey could not name any symptoms that endometriosis can cause. Almost ¾ of men in the study did not know what endometriosis was [1].

Next, the difficulty in diagnosing it

Endometriosis is difficult to diagnose. The gold-standard and most certain way to diagnose it is to go through surgery. This surgery does aim to be as ‘minimally invasive’ as possible and is done through laparoscopic (keyhole) surgery. But naturally, this can deter a lot of women from going through this due to the risks of surgery, but also because of fear and worry.

The first less invasive investigation your doctor will most likely organise is a transvaginal ultrasound. This is an ultrasound where a probe is inserted into the vagina, which allows for a better view of the organs in the pelvis than can be obtained through a transabdominal (through the stomach) ultrasound. This type of ultrasound works well in someone who has one or more endometriomas.

Endometriomas are like large cysts, that contain tissue similar to the uterus lining, that can develop as part of endometriosis. The sensitivity of ultrasound to pick up endometriomas is high (estimated to be about 93%) [2]. However, not everyone with endometriosis will have endometriomas! It is estimated that about 17-44% of women with endometriosis will have endometriomas [3]. It can be really hard to see more subtle changes on ultrasound, particularly any endometriosis that is around the ligaments in the pelvis.

A MRI of the pelvis can be used to get an image of the lower abdomen and pelvis. It’s usually easier to see ovarian endometriosis on MRI, and usually deep endometriosis can be seen, especially when it involves the bladder or bowel [4] [5]. MRI will normally pick up about 90% of endometriosis, but this depends on where the endometriosis is in the pelvis and how much change the endometriosis has caused [6].

Thirdly, a Retroverted Uterus

A retroverted uterus can limit the ultrasound exam and make it harder to see endometriosis deposits. A retroverted uterus is when the uterus is tipped backwards and is tipped towards the rectum, rather than tilting forwards towards the bladder (this would be an anteverted uterus). This can be a normal variant (it’s estimated that about 20-30% of women may naturally have this) but it can also be caused by the endometriosis process.

Lastly, Why Surgery?

The gold standard for diagnosis is a diagnostic laparoscopy. Diagnostic laparoscopy simply means keyhole surgery (laparoscopy) with the aim of coming to a diagnosis (diagnostic), rather than treating something. Having keyhole surgery allows the surgeon to directly view inside someone’s pelvis. It also allows the surgeon to take biopsies and images of what’s going on inside.

Endometrial deposits, especially subtle changes, can be much easier to see under direct vision than through scans. Imagine if airport security was looking for something relatively small or something that was well dispersed in your suitcase, for example if you spilled some small sweets in your bag. They could put your suitcase through the X-ray to scan it, but it might be hard to see the small sweets, but actually getting an actual look inside your suitcase will help them see the sweets clearly and is much more efficient.

If you’re at the point of being referred to surgery, or waiting for surgery, it’s really helpful to make sure you discuss all the risks and benefits of the surgery. Discussing the procedure in detail with your surgeon or operating team can be a really helpful way to resolve any queries and alleviate any worries.

Where can I get further information?

There are many useful websites, resources and great reads out there for further information! We’ve listed just a few below:


[2] Nisenblat V, Bossuyt PM, Farquhar C, et al. Imaging modalities for the non-invasive diagnosis of endometriosis. Cochrane Database Syst Rev. 2016 Feb 26;(2):CD009591.

[3] Gałczyński K, Jóźwik M, Lewkowicz D, Semczuk-Sikora A, Semczuk A. Ovarian endometrioma - a possible finding in adolescent girls and young women: a mini-review. J Ovarian Res. 2019 Nov 7;12(1):104. doi: 10.1186/s13048-019-0582-5.

[4] European Society of Human Reproduction and Embryology Endometriosis Guideline Development Group. Guideline on the management of women with endometriosis. Feb 2022.

[5] National Institute for Health and Care Excellence. Endometriosis: diagnosis and management. September 2017.

[6] Bazot M, Darai E, Hourani R, et al. Deep pelvic endometriosis: MR imaging for diagnosis and prediction of extension of disease. Radiology. 2004 Aug;232(2):379-89.

27 views0 comments

Recent Posts

See All


bottom of page